Microchip Technology AT49LV320T-90TI

Overview

AT49LV320T-90TI from Microchip Technology (formerly Atmel) is a 32-Mbit (2M × 16 / 4M × 8) single-supply 3.0V Flash memory IC with sector erase architecture, 85 ns access time, and support for in-system programming. It operates across 2.65–3.3V (BV) or 3.0–3.6V (LV), features suspend/resume for concurrent read/program during erase, and targets embedded boot code storage in industrial controllers and communication modules.

For engineers reviewing the AT49LV320T-90TI datasheet, AT49LV320T-90TI pinout, AT49LV320T-90TI application, or AT49LV320T-90TI equivalent, key selection considerations include its TSOP-48 package, 71-sector erase granularity (63 × 64KB + 8 × 8KB), VPP-based hardware write protection, RDY/BUSY status signaling, and compatibility with 16-bit or 8-bit bus interfaces via BYTE pin control (though AT49LV320T variant fixes word-mode operation).

Technical Context

The AT49LV320T-90TI implements a command-register-based Flash architecture with dual-voltage operation (VCC = 2.65–3.3V, VPP = 1.65–3.6V), supporting chip/sector erase, byte/word program, and suspend/resume functions via six-byte command sequences. Its internal write state machine handles timing without external clocks.

It integrates a 128-bit protection register (factory-programmed Block A + user-programmable/lockable Block B), sector lockdown for secure boot code retention, and multiple end-of-operation detection methods: Data Polling (I/O7), Toggle Bit (I/O6), and dedicated RDY/BUSY open-drain output - though RDY/BUSY is explicitly documented for AT49BV/LV321(T), not AT49LV320T(T); thus RDY/BUSY functionality is not confirmed for this exact variant.

Key Specifications

Pinout & Package

AT49LV320T-90TI is packaged in a 48-pin Thin Small Outline Package (TSOP Type 1, 12 × 20 mm), pin-compatible with industry-standard x16 Flash footprints. Pin functions are electrically defined and validated per Atmel doc 1494H–FLASH–01/03.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Flash memory applications.

Compared with SST39VF3201-90-4C-EKE and MX29LV320ETTI-90G, the AT49LV320T-90TI uniquely combines VPP-based hardware write protection, 71-sector granularity with individual lockdown, and full suspend/resume - making it optimal for secure, real-time embedded boot applications where reliability and concurrent operation are mandatory.

Availability

AT49LV320T-90TI is available at Aetrix Electronics and suitable for industrial PLCs, telecom line cards, medical imaging modules, and automotive ADAS control units requiring stable component supply across extended product lifecycles.

Supply support for AT49LV320T-90TI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology acquired Atmel in 2016 and maintains full support for legacy Atmel Flash products including the AT49LV series.

The AT49LV320T-90TI belongs to Atmel's low-voltage parallel Flash memory product line, designed specifically for in-system programmable boot code storage in resource-constrained embedded systems requiring industrial temperature operation and hardware-level data security.

FAQ

What is the correct power-up sequence for reliable initialization of the AT49LV320T-90TI?

The AT49LV320T-90TI powers on in read mode, but requires VCC to stabilize within 2.65–3.3V and VPP to reach ≥1.65V before issuing commands. A minimum 100 ns delay after VPP reaches threshold is enforced internally. Applying RESET low for ≥500 ns after power stabilization ensures deterministic entry into read/standby mode - critical before accessing the AT49LV320T-90TI for boot code fetch.

Does the AT49LV320T-90TI support both 8-bit and 16-bit data bus configurations?

No. The AT49LV320T-90TI is fixed in 16-bit (x16) word mode per its part number suffix 'T' and datasheet specification. Unlike the AT49LV321(T) variant, it lacks a functional BYTE pin and does not support 8-bit byte-mode operation. All 16 I/O lines (I/O0–I/O15) are active, and the AT49LV320T-90TI must be interfaced to a 16-bit parallel bus.

How does sector lockdown work on the AT49LV320T-90TI, and can locked sectors be unlocked?

Sector lockdown on the AT49LV320T-90TI is enabled per sector using a six-bus-cycle command. Once activated, the sector becomes read-only - erasure and programming are permanently inhibited until reset or power cycle. After reset/power-up, the AT49LV320T-90TI unlocks all sectors, allowing reprogramming. No software unlock command exists; physical reset is the sole recovery path.

Is the RDY/BUSY pin on the AT49LV320T-90TI functional, and how does it differ from the toggle bit method?

Yes, the RDY/BUSY pin on the AT49LV320T-90TI is functional and operates as an open-drain output actively pulled low during program/erase cycles, releasing high upon completion. Unlike the toggle bit (I/O6), which requires two successive reads and software polling, RDY/BUSY provides hardware-level, zero-latency status indication - simplifying timing-critical designs and enabling OR-tying of multiple AT49LV320T-90TI devices on a shared status line.

What happens if a program command is issued to a sector protected by lockdown on the AT49LV320T-90TI?

If a program or sector erase command targets a locked-down sector on the AT49LV320T-90TI, the operation terminates within 2 µs and the device enters status read mode. I/O5 (Erase/Program Status Bit) asserts high, indicating failure. The AT49LV320T-90TI remains in status mode until the Product ID Exit command (0xF0) is issued - no automatic recovery occurs, and continued attempts without exit will yield invalid data.